EMBO Molecular Medicine

All articles accepted from 14 August 2012 are published under the terms of the Creative Commons Attribution License. Articles accepted before this date were published under the agreement as stated in the final article.

Review Series: small RNAs

Small RNAs or non-coding RNAs are functional RNAs that are not translated into proteins. They include tRNAs, rRNAs, snoRNAs, piRNAs, long non-coding RNAs and microRNAs (miRNAs). They are highly abundant and involved in many different cellular processes. miRNAs are usually very short (22nt) and act as post-transcriptional regulators by binding to a complementary sequence on target mRNAs, most of the time resulting in the target silencing or degradation. Increasingly, deregulated miRNAs are found intimately involved in human diseases, in cancer, hearing loss, but also neurodegenerative or cardiovascular diseases. They can also act as circulating biomarkers and are being developed for therapy. This Review Series covers all those different aspects of small RNAs in diseases.

MicroRNAs have been implicated in the aging process. This review discusses recent findings on the roles of microRNAs in conditions associated with aging, with a focus on cardiovascular and neurodegenerative diseases.

MicroRNAs have been implicated in ear development, function and pathologic conditions like deafness and otitis media. This Review discusses the clinical and therapeutic consequences of understanding the role of miRNAs in the ear.

Aberrant microRNA expression signatures are a hallmark of several diseases, including cancer. miRNAs are getting more and more implicated in tumor development, progression and response to therapy, suggesting their possible use as diagnostic, prognostic and predictive biomarkers. This Review summarizes our current knowledge and addresses the future prospects of miRNAs in oncology.

The underlying molecular causes of alcohol addiction remain unclear. Many miRNAs are found modulated in the nucleus accumbens of rats chronically treated with alcohol. Specifically, miR-382 is shown to regulate alcohol intake via DRD1 and DeltaFosB.

C-Myc overexpression is one of the most common aberrations in human cancers. Here, the authors identified miR-33b as a negative regulator of c-Myc and show that lovastatin upregulates its expression resulting in suppressed c-Myc expression accompanied by reduced tumor growth and increased survival in mice.

Hypercholesterolemia patients are usually prescribed statins, which induces miR-33 and regulates HDL cholesterol in the liver. Baldan and colleagues show here that miR-33 also modulates expression of hepatic sterol transporters and thus contributes to the hepatotoxic effects of statins in patients.

Cardiac hypertrophy accompanies the majority of disease- and age-related cardiac pathologies. Here, the authors report that miR-142, which targets mediators of growth and survival, ensures that these signals remain quiescent in the non-stressed heart.

Systemic lupus erythematosus (SLE) is a potentially fatal systemic autoimmune disease. The authors show that pharmacological in vivo inhibition of miR-21 using seed-targeting LNAs can alter the course of the disease in mice.

The authors report a blood test for the diagnosis of NSCLC of potential impact in the design of screening programmes for early detection in at-risk individuals, with perspective improvement in the prognosis of the disease.

Germ-line mutations in the BRCA1 gene strongly predispose women to breast cancer and the BRCA1 protein is absent or present at very low levels in about one third of sporadic breast cancers. This study reports the identification of two microRNAs negatively regulating BRCA1 expression.

The authors suggest that miR-1, miR-133, and miR-206 represent valuable biomarkers not only for the diagnosis of DMD onset and progression but also for monitoring the outcomes of therapeutic interventions in humans.

Endometriosis is a common, benign gynecological disorder, which is a frequent cause of chronic pelvic pain and infertility in 5–15% of reproductive age women. This study identified a novel gene mutation, which is associated with up to one third of endometriosis cases.